Balloon catheters are used in a variety of different medical procedures, notably in the field of peripheral intervention. A typical balloon catheter includes an elongate body or shaft having an inflatable balloon attached near a distal end thereof. An inflation fluid is supplied via a longitudinally extending lumen in the shaft to inflate the balloon for purposes such as deforming blockages in veins or arteries, expanding implantable devices such as stents, and blocking fluid flow through body lumens. A second lumen is often provided through at least a portion of the balloon catheter, such that the device can be slid over a wire guide to a location of interest within a patient.
It is common for balloon inflation lumens and wire guide lumens in a balloon catheter to be formed by separate tubular elements that are attached to one another via adhesives and the like. Manufacturing balloon catheters can be relatively labor intensive given the need to attach a number of different parts, some of which can be quite small. European Patent Application Publication No. 0268068 to Marangoni discloses one example angioplasty catheter, where two coaxial lumens are formed in separate tubes attached to one another, and a balloon is attached to both the outer tube and the inner tube, providing both an outer inflation lumen and an inner lumen for the apparent purpose of guiding the device over a wire guide or the like. While Marangoni may work suitably in its intended environment, there is always room for improvement, particularly with regard to ease of manufacturing and design complexity.